Castle Hill is located 120 km west of Christchurch close to the Great Alpine Highway 73, between Darfield and Arthur's Pass in New Zealand's South Island. Described as one of the world’s finest bouldering locations, Castle Hill is renowned for its stunning limestone rock formations nestled in grassy paddocks, each filled with hundreds of limestone boulders and thousand’s of named bouldering problems (climbing paths). The early Europeans named it “Castle Hill” because the imposing array of limestone boulders reminded them of old, run-down stone castle. Indeed, the front of ChristChurch Cathedral in Christchurch was made from Castle Hill limestone.